<!DOCTYPE html>
<html>
<body>
<div unselectable="on" style="background:#CCC;" >unselectable=on </div>
<br/>
<div style="background:#CCC;-webkit-user-select:none;" >-webkit-user-select:none;</div>
<br/>
<div style="background:#CCC;-moz-user-select:none;" >-moz-user-select:none;</div>
<br/>
<div style="background:#CCC;" onselectstart="return false;">onselectstart="return false;"</div>
</body>
</html>